drivers/ram/stm32_sdram.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
   4  * Author(s): Vikas Manocha, <vikas.manocha@st.com> for STMicroelectronics.
   5  */
   6
   7 #include <common.h>
   8 #include <clk.h>
   9 #include <dm.h>
  10 #include <init.h>
  11 #include <log.h>
  12 #include <ram.h>
  13 #include <asm/io.h>
  14 #include <dm/device_compat.h>
  15 #include <linux/bitops.h>
  16 #include <linux/delay.h>
  17
  18 #define MEM_MODE_MASK   GENMASK(2, 0)
  19 #define SWP_FMC_OFFSET 10
  20 #define SWP_FMC_MASK    GENMASK(SWP_FMC_OFFSET+1, SWP_FMC_OFFSET)
  21 #define NOT_FOUND       0xff
  22
  23 struct stm32_fmc_regs {
  24         /* 0x0 */
  25         u32 bcr1;       /* NOR/PSRAM Chip select control register 1 */
  26         u32 btr1;       /* SRAM/NOR-Flash Chip select timing register 1 */
  27         u32 bcr2;       /* NOR/PSRAM Chip select Control register 2 */
  28         u32 btr2;       /* SRAM/NOR-Flash Chip select timing register 2 */
  29         u32 bcr3;       /* NOR/PSRAMChip select Control register 3 */
  30         u32 btr3;       /* SRAM/NOR-Flash Chip select timing register 3 */
  31         u32 bcr4;       /* NOR/PSRAM Chip select Control register 4 */
  32         u32 btr4;       /* SRAM/NOR-Flash Chip select timing register 4 */
  33         u32 reserved1[24];
  34
  35         /* 0x80 */
  36         u32 pcr;        /* NAND Flash control register */
  37         u32 sr;         /* FIFO status and interrupt register */
  38         u32 pmem;       /* Common memory space timing register */
  39         u32 patt;       /* Attribute memory space timing registers  */
  40         u32 reserved2[1];
  41         u32 eccr;       /* ECC result registers */
  42         u32 reserved3[27];
  43
  44         /* 0x104 */
  45         u32 bwtr1;      /* SRAM/NOR-Flash write timing register 1 */
  46         u32 reserved4[1];
  47         u32 bwtr2;      /* SRAM/NOR-Flash write timing register 2 */
  48         u32 reserved5[1];
  49         u32 bwtr3;      /* SRAM/NOR-Flash write timing register 3 */
  50         u32 reserved6[1];
  51         u32 bwtr4;      /* SRAM/NOR-Flash write timing register 4 */
  52         u32 reserved7[8];
  53
  54         /* 0x140 */
  55         u32 sdcr1;      /* SDRAM Control register 1 */
  56         u32 sdcr2;      /* SDRAM Control register 2 */
  57         u32 sdtr1;      /* SDRAM Timing register 1 */
  58         u32 sdtr2;      /* SDRAM Timing register 2 */
  59         u32 sdcmr;      /* SDRAM Mode register */
  60         u32 sdrtr;      /* SDRAM Refresh timing register */
  61         u32 sdsr;       /* SDRAM Status register */
  62 };
  63
  64 /*
  65  * NOR/PSRAM Control register BCR1
  66  * FMC controller Enable, only availabe for H7
  67  */
  68 #define FMC_BCR1_FMCEN          BIT(31)
  69
  70 /* Control register SDCR */
  71 #define FMC_SDCR_RPIPE_SHIFT    13      /* RPIPE bit shift */
  72 #define FMC_SDCR_RBURST_SHIFT   12      /* RBURST bit shift */
  73 #define FMC_SDCR_SDCLK_SHIFT    10      /* SDRAM clock divisor shift */
  74 #define FMC_SDCR_WP_SHIFT       9       /* Write protection shift */
  75 #define FMC_SDCR_CAS_SHIFT      7       /* CAS latency shift */
  76 #define FMC_SDCR_NB_SHIFT       6       /* Number of banks shift */
  77 #define FMC_SDCR_MWID_SHIFT     4       /* Memory width shift */
  78 #define FMC_SDCR_NR_SHIFT       2       /* Number of row address bits shift */
  79 #define FMC_SDCR_NC_SHIFT       0       /* Number of col address bits shift */
  80
  81 /* Timings register SDTR */
  82 #define FMC_SDTR_TMRD_SHIFT     0       /* Load mode register to active */
  83 #define FMC_SDTR_TXSR_SHIFT     4       /* Exit self-refresh time */
  84 #define FMC_SDTR_TRAS_SHIFT     8       /* Self-refresh time */
  85 #define FMC_SDTR_TRC_SHIFT      12      /* Row cycle delay */
  86 #define FMC_SDTR_TWR_SHIFT      16      /* Recovery delay */
  87 #define FMC_SDTR_TRP_SHIFT      20      /* Row precharge delay */
  88 #define FMC_SDTR_TRCD_SHIFT     24      /* Row-to-column delay */
  89
  90 #define FMC_SDCMR_NRFS_SHIFT    5
  91
  92 #define FMC_SDCMR_MODE_NORMAL           0
  93 #define FMC_SDCMR_MODE_START_CLOCK      1
  94 #define FMC_SDCMR_MODE_PRECHARGE        2
  95 #define FMC_SDCMR_MODE_AUTOREFRESH      3
  96 #define FMC_SDCMR_MODE_WRITE_MODE       4
  97 #define FMC_SDCMR_MODE_SELFREFRESH      5
  98 #define FMC_SDCMR_MODE_POWERDOWN        6
  99
 100 #define FMC_SDCMR_BANK_1                BIT(4)
 101 #define FMC_SDCMR_BANK_2                BIT(3)
 102
 103 #define FMC_SDCMR_MODE_REGISTER_SHIFT   9
 104
 105 #define FMC_SDSR_BUSY                   BIT(5)
 106
 107 #define FMC_BUSY_WAIT(regs)     do { \
 108                 __asm__ __volatile__ ("dsb" : : : "memory"); \
 109                 while (regs->sdsr & FMC_SDSR_BUSY) \
 110                         ; \
 111         } while (0)
 112
 113 struct stm32_sdram_control {
 114         u8 no_columns;
 115         u8 no_rows;
 116         u8 memory_width;
 117         u8 no_banks;
 118         u8 cas_latency;
 119         u8 sdclk;
 120         u8 rd_burst;
 121         u8 rd_pipe_delay;
 122 };
 123
 124 struct stm32_sdram_timing {
 125         u8 tmrd;
 126         u8 txsr;
 127         u8 tras;
 128         u8 trc;
 129         u8 trp;
 130         u8 twr;
 131         u8 trcd;
 132 };
 133 enum stm32_fmc_bank {
 134         SDRAM_BANK1,
 135         SDRAM_BANK2,
 136         MAX_SDRAM_BANK,
 137 };
 138
 139 enum stm32_fmc_family {
 140         STM32F7_FMC,
 141         STM32H7_FMC,
 142 };
 143
 144 struct bank_params {
 145         struct stm32_sdram_control *sdram_control;
 146         struct stm32_sdram_timing *sdram_timing;
 147         u32 sdram_ref_count;
 148         enum stm32_fmc_bank target_bank;
 149 };
 150
 151 struct stm32_sdram_params {
 152         struct stm32_fmc_regs *base;
 153         u8 no_sdram_banks;
 154         struct bank_params bank_params[MAX_SDRAM_BANK];
 155         enum stm32_fmc_family family;
 156 };
 157
 158 #define SDRAM_MODE_BL_SHIFT     0
 159 #define SDRAM_MODE_CAS_SHIFT    4
 160 #define SDRAM_MODE_BL           0
 161
 162 int stm32_sdram_init(struct udevice *dev)
 163 {
 164         struct stm32_sdram_params *params = dev_get_platdata(dev);
 165         struct stm32_sdram_control *control;
 166         struct stm32_sdram_timing *timing;
 167         struct stm32_fmc_regs *regs = params->base;
 168         enum stm32_fmc_bank target_bank;
 169         u32 ctb; /* SDCMR register: Command Target Bank */
 170         u32 ref_count;
 171         u8 i;
 172
 173         /* disable the FMC controller */
 174         if (params->family == STM32H7_FMC)
 175                 clrbits_le32(&regs->bcr1, FMC_BCR1_FMCEN);
 176
 177         for (i = 0; i < params->no_sdram_banks; i++) {
 178                 control = params->bank_params[i].sdram_control;
 179                 timing = params->bank_params[i].sdram_timing;
 180                 target_bank = params->bank_params[i].target_bank;
 181                 ref_count = params->bank_params[i].sdram_ref_count;
 182
 183                 writel(control->sdclk << FMC_SDCR_SDCLK_SHIFT
 184                         | control->cas_latency << FMC_SDCR_CAS_SHIFT
 185                         | control->no_banks << FMC_SDCR_NB_SHIFT
 186                         | control->memory_width << FMC_SDCR_MWID_SHIFT
 187                         | control->no_rows << FMC_SDCR_NR_SHIFT
 188                         | control->no_columns << FMC_SDCR_NC_SHIFT
 189                         | control->rd_pipe_delay << FMC_SDCR_RPIPE_SHIFT
 190                         | control->rd_burst << FMC_SDCR_RBURST_SHIFT,
 191                         &regs->sdcr1);
 192
 193                 if (target_bank == SDRAM_BANK2)
 194                         writel(control->cas_latency << FMC_SDCR_CAS_SHIFT
 195                                 | control->no_banks << FMC_SDCR_NB_SHIFT
 196                                 | control->memory_width << FMC_SDCR_MWID_SHIFT
 197                                 | control->no_rows << FMC_SDCR_NR_SHIFT
 198                                 | control->no_columns << FMC_SDCR_NC_SHIFT,
 199                                 &regs->sdcr2);
 200
 201                 writel(timing->trcd << FMC_SDTR_TRCD_SHIFT
 202                         | timing->trp << FMC_SDTR_TRP_SHIFT
 203                         | timing->twr << FMC_SDTR_TWR_SHIFT
 204                         | timing->trc << FMC_SDTR_TRC_SHIFT
 205                         | timing->tras << FMC_SDTR_TRAS_SHIFT
 206                         | timing->txsr << FMC_SDTR_TXSR_SHIFT
 207                         | timing->tmrd << FMC_SDTR_TMRD_SHIFT,
 208                         &regs->sdtr1);
 209
 210                 if (target_bank == SDRAM_BANK2)
 211                         writel(timing->trcd << FMC_SDTR_TRCD_SHIFT
 212                                 | timing->trp << FMC_SDTR_TRP_SHIFT
 213                                 | timing->twr << FMC_SDTR_TWR_SHIFT
 214                                 | timing->trc << FMC_SDTR_TRC_SHIFT
 215                                 | timing->tras << FMC_SDTR_TRAS_SHIFT
 216                                 | timing->txsr << FMC_SDTR_TXSR_SHIFT
 217                                 | timing->tmrd << FMC_SDTR_TMRD_SHIFT,
 218                                 &regs->sdtr2);
 219
 220                 if (target_bank == SDRAM_BANK1)
 221                         ctb = FMC_SDCMR_BANK_1;
 222                 else
 223                         ctb = FMC_SDCMR_BANK_2;
 224
 225                 writel(ctb | FMC_SDCMR_MODE_START_CLOCK, &regs->sdcmr);
 226                 udelay(200);    /* 200 us delay, page 10, "Power-Up" */
 227                 FMC_BUSY_WAIT(regs);
 228
 229                 writel(ctb | FMC_SDCMR_MODE_PRECHARGE, &regs->sdcmr);
 230                 udelay(100);
 231                 FMC_BUSY_WAIT(regs);
 232
 233                 writel((ctb | FMC_SDCMR_MODE_AUTOREFRESH | 7 << FMC_SDCMR_NRFS_SHIFT),
 234                        &regs->sdcmr);
 235                 udelay(100);
 236                 FMC_BUSY_WAIT(regs);
 237
 238                 writel(ctb | (SDRAM_MODE_BL << SDRAM_MODE_BL_SHIFT
 239                        | control->cas_latency << SDRAM_MODE_CAS_SHIFT)
 240                        << FMC_SDCMR_MODE_REGISTER_SHIFT | FMC_SDCMR_MODE_WRITE_MODE,
 241                        &regs->sdcmr);
 242                 udelay(100);
 243                 FMC_BUSY_WAIT(regs);
 244
 245                 writel(ctb | FMC_SDCMR_MODE_NORMAL, &regs->sdcmr);
 246                 FMC_BUSY_WAIT(regs);
 247
 248                 /* Refresh timer */
 249                 writel(ref_count << 1, &regs->sdrtr);
 250         }
 251
 252         /* enable the FMC controller */
 253         if (params->family == STM32H7_FMC)
 254                 setbits_le32(&regs->bcr1, FMC_BCR1_FMCEN);
 255
 256         return 0;
 257 }
 258
 259 static int stm32_fmc_ofdata_to_platdata(struct udevice *dev)
 260 {
 261         struct stm32_sdram_params *params = dev_get_platdata(dev);
 262         struct bank_params *bank_params;
 263         struct ofnode_phandle_args args;
 264         u32 *syscfg_base;
 265         u32 mem_remap;
 266         u32 swp_fmc;
 267         ofnode bank_node;
 268         char *bank_name;
 269         u8 bank = 0;
 270         int ret;
 271
 272         ret = dev_read_phandle_with_args(dev, "st,syscfg", NULL, 0, 0,
 273                                                  &args);
 274         if (ret) {
 275                 dev_dbg(dev, "%s: can't find syscon device (%d)\n", __func__, ret);
 276         } else {
 277                 syscfg_base = (u32 *)ofnode_get_addr(args.node);
 278
 279                 mem_remap = dev_read_u32_default(dev, "st,mem_remap", NOT_FOUND);
 280                 if (mem_remap != NOT_FOUND) {
 281                         /* set memory mapping selection */
 282                         clrsetbits_le32(syscfg_base, MEM_MODE_MASK, mem_remap);
 283                 } else {
 284                         dev_dbg(dev, "%s: cannot find st,mem_remap property\n", __func__);
 285                 }
 286
 287                 swp_fmc = dev_read_u32_default(dev, "st,swp_fmc", NOT_FOUND);
 288                 if (swp_fmc != NOT_FOUND) {
 289                         /* set fmc swapping selection */
 290                         clrsetbits_le32(syscfg_base, SWP_FMC_MASK, swp_fmc << SWP_FMC_OFFSET);
 291                 } else {
 292                         dev_dbg(dev, "%s: cannot find st,swp_fmc property\n", __func__);
 293                 }
 294
 295                 dev_dbg(dev, "syscfg %x = %x\n", (u32)syscfg_base, *syscfg_base);
 296         }
 297
 298         dev_for_each_subnode(bank_node, dev) {
 299                 /* extract the bank index from DT */
 300                 bank_name = (char *)ofnode_get_name(bank_node);
 301                 strsep(&bank_name, "@");
 302                 if (!bank_name) {
 303                         pr_err("missing sdram bank index");
 304                         return -EINVAL;
 305                 }
 306
 307                 bank_params = &params->bank_params[bank];
 308                 strict_strtoul(bank_name, 10,
 309                                (long unsigned int *)&bank_params->target_bank);
 310
 311                 if (bank_params->target_bank >= MAX_SDRAM_BANK) {
 312                         pr_err("Found bank %d , but only bank 0 and 1 are supported",
 313                               bank_params->target_bank);
 314                         return -EINVAL;
 315                 }
 316
 317                 debug("Find bank %s %u\n", bank_name, bank_params->target_bank);
 318
 319                 params->bank_params[bank].sdram_control =
 320                         (struct stm32_sdram_control *)
 321                          ofnode_read_u8_array_ptr(bank_node,
 322                                                   "st,sdram-control",
 323                                                   sizeof(struct stm32_sdram_control));
 324
 325                 if (!params->bank_params[bank].sdram_control) {
 326                         pr_err("st,sdram-control not found for %s",
 327                               ofnode_get_name(bank_node));
 328                         return -EINVAL;
 329                 }
 330
 331
 332                 params->bank_params[bank].sdram_timing =
 333                         (struct stm32_sdram_timing *)
 334                          ofnode_read_u8_array_ptr(bank_node,
 335                                                   "st,sdram-timing",
 336                                                   sizeof(struct stm32_sdram_timing));
 337
 338                 if (!params->bank_params[bank].sdram_timing) {
 339                         pr_err("st,sdram-timing not found for %s",
 340                               ofnode_get_name(bank_node));
 341                         return -EINVAL;
 342                 }
 343
 344
 345                 bank_params->sdram_ref_count = ofnode_read_u32_default(bank_node,
 346                                                 "st,sdram-refcount", 8196);
 347                 bank++;
 348         }
 349
 350         params->no_sdram_banks = bank;
 351         debug("%s, no of banks = %d\n", __func__, params->no_sdram_banks);
 352
 353         return 0;
 354 }
 355
 356 static int stm32_fmc_probe(struct udevice *dev)
 357 {
 358         struct stm32_sdram_params *params = dev_get_platdata(dev);
 359         int ret;
 360         fdt_addr_t addr;
 361
 362         addr = dev_read_addr(dev);
 363         if (addr == FDT_ADDR_T_NONE)
 364                 return -EINVAL;
 365
 366         params->base = (struct stm32_fmc_regs *)addr;
 367         params->family = dev_get_driver_data(dev);
 368
 369 #ifdef CONFIG_CLK
 370         struct clk clk;
 371
 372         ret = clk_get_by_index(dev, 0, &clk);
 373         if (ret < 0)
 374                 return ret;
 375
 376         ret = clk_enable(&clk);
 377
 378         if (ret) {
 379                 dev_err(dev, "failed to enable clock\n");
 380                 return ret;
 381         }
 382 #endif
 383         ret = stm32_sdram_init(dev);
 384         if (ret)
 385                 return ret;
 386
 387         return 0;
 388 }
 389
 390 static int stm32_fmc_get_info(struct udevice *dev, struct ram_info *info)
 391 {
 392         return 0;
 393 }
 394
 395 static struct ram_ops stm32_fmc_ops = {
 396         .get_info = stm32_fmc_get_info,
 397 };
 398
 399 static const struct udevice_id stm32_fmc_ids[] = {
 400         { .compatible = "st,stm32-fmc", .data = STM32F7_FMC },
 401         { .compatible = "st,stm32h7-fmc", .data = STM32H7_FMC },
 402         { }
 403 };
 404
 405 U_BOOT_DRIVER(stm32_fmc) = {
 406         .name = "stm32_fmc",
 407         .id = UCLASS_RAM,
 408         .of_match = stm32_fmc_ids,
 409         .ops = &stm32_fmc_ops,
 410         .ofdata_to_platdata = stm32_fmc_ofdata_to_platdata,
 411         .probe = stm32_fmc_probe,
 412         .platdata_auto_alloc_size = sizeof(struct stm32_sdram_params),
 413 };